A new generation of broadband communication satellite with hlly regenerative digitalpayloads and onboard switching is currently being planned and designed. These satellites willprovide much more capacity and flexibility than current transponding satellites.Most of the geostationary broadband satellite systems will use Multiple FrequencyTime Division Multiple Access (MF-TDMA) uplinks and will support a large number ofterminals. In order to effectively use the allocated bandwidth, an efficient, dynamic, MediaAccess Control (MAC) protocol that minimizes complexity on the satellite is required..